Application And Research On Closed-end Dust Removal System Of Comprehensive Mechanized Heading Face

Dust concentration in comprehensive mechanized heading face must be controlled in a proper range to ensure protecting workers occupational safety and health and enterprise safety production because dust production of comprehensive mechanized heading face is larger, and even exceeds the prescribed limit of "coal mine safety regulation". In this dissertation, closed-end dust-removing system of comprehensive mechanized heading face is proposed, combining theoretical analysis, numerical simulation, experimental measuration and application on-spot. Finally, the field application showed satisfactory results.k-εthree-dimensional turbulence model for single-phase air flow and k-ε-(?)-kp dual phase gas phase turbulent-dust particles phase turbulent model are established, hybrid scheme and SIMPLE algorithm based on collocated grid are numerical solution of two-phase flow for gas and dust particles. Numerical simulation on air-flowing field and dust flowing field in comprehensive mechanized heading face is made by single-hybrid- negative pressure pumps formula and wall-attachment-fan drum closed-end dust-removing and cleaning system through ANSYS FLUENT software, therefore, the change law of air-flowing field and dust flowing field using closed-end dust-removing and cleaning system is obtained in pre and post comprehensive mechanized heading face, and the theoretical foundation for analysis of closed-end dust-removing and cleaning system in comprehensive mechanized heading face is provided.Spray characteristics experiment and spray and dust reduction experiment are finished under simulation real wind speed in comprehensive mechanized heading face by using self-designed manufactured experimental device, and the mechanism of nozzle spray and spray and dust reduction are analyzed. Various nozzles law in spray field of the droplet size spray flow structure under different pressure and different wind speed is determined, the corresponding relation between different droplet size and coal dust droplet size captured isΔD≈0.12·Ddust-free droplet. NO.1 and NO.2 hybrid nozzles containing X style diversion core of wide angle arch with hole diameters of 1.6 mm and 2.4 mm, which are used by spray and dust reduction device in outer fully-mechanized coal winning machine through the experiment result and the size of fully-mechanized coal winning machine, and spray is taking when water pressure is 4MPa.Closed-end dust-removing and cleaning system in comprehensive mechanized heading face that composed of spray and dust reduction device in outer fully-mechanized coal winning machine and closed-end dust-removing and cleaning device is desired according to production situation, dust production feature, dust distributing law, nozzle selection in outer fully-mechanized coal winning machine and nozzle pressure ect. in 3 F 506 haulage roadway comprehensive mechanized heading face of GaoZhuang Coal Mine. Finally, the field demonstration test results show that closed-end dust-removing and cleaning system in comprehensive mechanized heading face have acquired fine dedusting effect.